ell-disposed but rather unyielding minds did not quite understand
at first how, if the moon invariably shows the same face to the earth
during her revolution, she describes one turn round herself in the same
period of time. To such it was answered--"Go into your dining-room, and
turn round the table so as always to keep your face towards the centre;
when your circular walk is ended you will have described one circle
round yourselves, since your eye will have successively traversed every
point of the room. Well, then, the room is the heavens, the table is the
earth, and you are the moon!"

And they go away delighted with the comparison.

Thus, then, the moon always presents the same face to the earth; still,
to be quite exact, it should be added that in consequence of certain
fluctuations from north to south and from west to east, called
libration, she shows rather more than the half of her disc, about 0.57.

When the ignoramuses knew as much as the director of the Cambridge
Observatory about the moon's movement of rotation they began to make
themselves uneasy about her movement of revolution round the earth, and
twenty scientific reviews quickly gave them the information they wanted.
They then learnt that the firmament, with its infinite stars, may be
looked upon as a vast dial upon which the moon moves, indicating the
time to all the inhabitants of the earth; that it is in this movement
that the Queen of Night shows herself in her different phases, that she
is full when she is in opposition with the sun--that is to say, when the
three bodies are on a line with each other, the earth being in the
centre; that the moon is new when she is in conjunction with the
sun--that is to say, when she is between the sun and the earth; lastly,
that the moon is in her first or last quarter when she makes, with the
sun and the earth, a right angle of which she occupies the apex.

Some perspicacious Yankees inferred in consequence that eclipses could
only take place at the periods of conjunction or opposition, and their
reasoning was just. In conjunction the moon can eclipse the sun, whilst
in opposition it is the earth that can eclipse him in her turn; and the
reason these eclipses do not happen twice in a lunar month is because
the plane upon which the moon moves is elliptical like that of the
earth.

As to the height which the Queen of Night can attain above the horizon,
the letter from the Observatory of Cambridge contained all